Über das Isochinuclidin

Renin inhibitors containing a pyridyl amino diol derived C-terminus

“…. A solution of 6.85 g (27.9 mmol) of O-methyl-L-tyrosine methyl ester, 6.80 g (27.9 mmol) of cis-4-[ (tert-butyloxycarbonyl) amino] cyclohexanecarboxylic acid (20),19 and 17.9 mL (139.50 mmol) of triethylamine in 250 mL of dry DMF was treated with 28 mL of a 50 % solution of n-propanephosphonic anhydride in ethyl acetate at 0 °C. The mixture was stirred for 18 h and then quenched by pouring into water.…”

AZABICYCLOALKANES. 2-AZABICYCLO[3·3·1]NONANE1,2

“…Three different methods were used for the preparation of the lactam (VI) of ds-3-aminocyclohexaneacetic acid. The first method followed the procedure used by others (8,13) for the reduction of an amino acid containing an aromatic amino group to its corresponding hexahydro derivative. The hydrochloride of ethyl m-aminophenylacetate was hydrogenated over platinum at 60-70°in ethanol to give a mixture of the cis and trans hexahydro esters (V) in the ratio of about 3:7. By heating this mixture at 200°in ethanol the cis ester was converted into the lactam (VI) and a majority of the trans ester was recovered unchanged.…”

“…When the thiolactam was refluxed with Raney nickel in absolute ethanol the product was the N-ethyl derivative (IX) . 8 The alkylation of amines by alcohols has been studied extensively at 150-200°( 17) but apparently the method has not been used at lower temperatures; although it has been observed that aniline was alkylated by ethanol during the reduction of nitrobenzene under similar conditions (18). A sample of the secondary amine (VIII) was alkylated to (IX) under hydrogen, thus demonstrating that the process is actually one of direct alkylation rather than the possible reductive alkylation via the acetaldehyde which may be generated by refluxing the ethanol solution open to the air or in contact with a hydrogen acceptor such as the aldimine form -CH=N- (19).…”

“…The azabicycloalkanes described in this work have been tested for possible 7 Ruzicka (23) has recently applied LiAlER to lactam reduction and obtained 60-95% yields of the polymethylene imines. 8 In early experiments a less active catalyst than that described by Adkins and Pavlic (20) was used. The results have not been clarified as yet since the products seemed to be a mixture of (IX) and the aldimine -CH=Nor its trimer.…”